Previously, my K10 has worked flawlessly in the hottest of conditions. Recently at all the venues I work at, the QSC will just stop working after about 3 - 3.5 hours of use. No matter which input I use, the signal light is blinking and the fan is still spinning. The audio just stops. The next day, I turn it on and boom, it works again but only for another 3 hours straight. Any ideas?